TWI512033B - Liquid state resin composition - Google Patents

Description

Liquid resin composition

The present invention relates to a liquid resin composition, and more particularly to a liquid resin composition suitable for sealing a Flip Chip type semiconductor element.

A COF (Chip On Film) package in which a semiconductor device of a semiconductor device such as a liquid crystal driver IC or the like is further increased in density and high in power is used, and Flip Chip Bonding is used. In general, the flip chip bonding method bonds a semiconductor element and a substrate with a bump, and the gap between the semiconductor element and the substrate is sealed with a liquid semiconductor encapsulant called an underfill material.

In recent years, in order to meet the demand for higher density and higher power of liquid crystal drive ICs, circuit patterns mounted on liquid crystal drive ICs are gradually moving toward fine pitch. Due to the high voltage accompanying the fine pitch and high power, there is a concern that migration between circuits is caused. Migration refers to a phenomenon in which a metal of a circuit pattern is eluted due to an electrochemical reaction, resulting in a decrease in resistance value. Fig. 1 is a schematic view showing the migration in the case where the electrode is copper (Cu). The migration system first dissolves Cu at the anode 2 via the reaction formula: Cu+2(OH ^- )→2(CuOH). On the substrate 1, Cu(OH) is in the direction of the solid arrow, that is, in the direction toward the cathode 3. Moving, at the cathode 3, on the substrate 1 via the reaction formula: CuOH + H ₃ O ⁺ → Cu + 2H ₂ O, Cu is deposited in the direction of the dotted arrow, that is, in the direction of the anode 2. Typically, the circuit pattern based underfill material to the liquid resin composition composed of an epoxy resin for sealing, but would epoxy resin absorbent by H ₂ O from the OH ^- or H ₃ O ⁺ and lead migrate . In addition, if there is Cl ^- ions in the environment, the migration will be accelerated. This Cl ^- ion is typically present as a dopant for the epoxy resin. If migration occurs, the resistance between the anode and the cathode of the circuit pattern becomes low, and if migration occurs, the anode and the cathode are short-circuited. Further, Cu(OH), specifically, in the case of Cu(OH) ₂ and Cu(OH) ⁺ , when Cu(OH) ₂ is used, it moves toward the cathode side due to the difference in concentration, and is Cu ( When OH) ⁺ , electromigration is performed.

Patent Document 1 reports a resin composition for preventing migration, which composition contains an ionic binder selected from benzotriazoles, and three And at least one substance of the same type of isocyanuric acid.

However, when a benzotriazole or the like is dispersed in an epoxy resin, there is a problem in that it is not used as an underfill due to thickening due to a hardening reaction during storage.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2008-98646

An object of the present invention is to prevent migration of a liquid resin composition after hardening, and to suppress adhesion of a liquid resin composition during storage. Therefore, an object of the present invention is to provide a highly reliable liquid resin composition which is excellent in storage characteristics and excellent in migration resistance after curing.

The present invention relates to a liquid resin composition which solves the above problems by having the following constitution.

[1] A liquid resin composition comprising:

(A) liquid epoxy resin,

(B) hardener, and

(C) a xanthine represented by the formula (1),

(wherein R ₁ , R ₂ and R ₃ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms).

[2] The liquid resin composition according to the above [1], wherein the component (C) is at least one selected from the group consisting of caffeine, theophylline, theobromine, and para-xanthine.

[3] The liquid resin composition according to the above [1], which further comprises (D) a curing accelerator.

[4] The liquid resin composition according to the above [1], which further comprises (E) a coupling agent.

[5] The liquid resin composition according to the above [1], which further comprises (F) a filler.

[6] The liquid resin composition according to the above [1], which further comprises (G) a rubber component.

[7] The cured product of the liquid resin composition according to the above [1], wherein the component (C) is 0.05 to 12 parts by mass based on 100 parts by mass of the liquid resin composition.

[8] A liquid semiconductor sealing agent comprising the liquid resin composition according to [1] above.

[9] A semiconductor device comprising a flip chip type semiconductor device which is sealed by using the liquid semiconductor sealing agent according to [8] above.

According to the invention [1], it is possible to provide a liquid resin composition which is excellent in storage characteristics and excellent in migration resistance after curing.

According to the invention [8], it is possible to easily provide a highly reliable semiconductor device excellent in migration resistance.

The liquid resin composition of the present invention is characterized by comprising:

(A) liquid epoxy resin,

(B) hardener, and

(C) a xanthine represented by the formula (1),

(wherein R ₁ , R ₂ and R ₃ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms).

Examples of the component (A) include liquid bisphenol A epoxy resin, liquid bisphenol F epoxy resin, liquid naphthalene epoxy resin, liquid amine phenol epoxy resin, and liquid. Hydrogenated bisphenol type epoxy resin, liquid alicyclic epoxy resin, liquid alcohol ether type epoxy resin, liquid cyclic aliphatic epoxy resin, liquid bismuth epoxy resin, liquid helium oxygen An alkyl epoxy resin or the like is preferably a liquid bisphenol A epoxy resin, a liquid bisphenol F epoxy resin, or a liquid in view of curability, heat resistance, adhesion, and durability. An amine phenol type epoxy resin or a liquid siloxane oxide type epoxy resin. From the standpoint of adjusting the viscosity, the epoxy equivalent is preferably from 80 to 250 g/eq. As a commercial item, for example, a bisphenol A type epoxy resin (product name: YDF8170) manufactured by Nippon Steel Chemical Co., Ltd., a bisphenol F type epoxy resin manufactured by Nippon Steel Chemical Co., Ltd. (product name: YDF870GS), Mitsubishi Chemically available amine phenol type epoxy resin (model: JER630, JER630LSD), DIC naphthalene type epoxy resin (product name: HP4032D), Shin-Etsu Chemical's oxime-based epoxy resin (product name: TSL9906). The component (A) may be used singly or in combination of two or more.

The component (B) may, for example, be an acid anhydride, an amine-based curing agent or a phenol-based curing agent, and is preferably an acid anhydride from the viewpoint of good reactivity (curing rate) and imparting an appropriate viscosity. Examples of the acid anhydride include methyltetrahydrophthalic anhydride, methylbutene tetrahydrofurfuric anhydride, methylhexahydrophthalic anhydride, alkylated tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylnorbornene. An acid anhydride, an alkenyl substituted succinic anhydride, a methyl nadic anhydride, glutaric anhydride or the like is preferably methylbutene tetrahydrophthalic anhydride. The amine-based curing agent may, for example, be a chain aliphatic amine, a cyclic aliphatic amine, a fatty aromatic amine or an aromatic amine, and is preferably an aromatic amine. The commercially available product may, for example, be an acid anhydride (Model: YH306, YH307) manufactured by Mitsubishi Chemical Corporation, or an amine hardener (KAYAHARD A-A) manufactured by Nippon Kasei Co., Ltd., or the like. Ingredient (B) may be used alone or in combination of two or more.

The component (C) is a xanthine represented by the formula (1).

(wherein R ₁ , R ₂ and R ₃ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), and the viscosity of the liquid resin composition during storage is suppressed, and the cured resin is cured. Increased migration resistance. In the component (C), R ₁ , R ₂ and R ₃ in the formula (1) are each independently a hydrogen atom or an alkyl group having 1 carbon atom; more preferably, it is selected from the formula ( 2)

Caffeine,

Formula (3)

Theophylline,

Formula (4)

Theobromine and formula (5)

At least one of the groups formed by the parasitic jaundice.

The liquid resin composition preferably has an acid anhydride equivalent of (B) component of from 0.6 to 1.2, more preferably from 0.65 to 1.1, from the viewpoint of good reactivity and reliability, with respect to the epoxy equivalent of the component (A). . When it is 0.6 or more, the PCT test of the reactive and cured liquid resin composition is excellent in moisture resistance reliability and migration resistance. On the other hand, when it is 1.2 or less, the viscosity increase ratio does not become too high. , but will inhibit the occurrence of voids.

The component (C) is preferably contained in an amount of from 0.05 to 12 parts by mass, more preferably from 0.1 to 10 parts by mass, even more preferably from 0.1 to 6 parts by mass, per 100 parts by mass of the liquid resin composition. When the amount is 0.1 part by mass or more, the lead corrosion resistance is good, and when it is 12 parts by mass or less, the increase in the viscosity increase ratio of the liquid resin composition can be suppressed. The component (C) may be, for example, a reagent commercially available from Wako Pure Chemical Industries.

Further, the component (C) is preferably contained in an amount of from 0.05 to 12 parts by mass, more preferably from 0.1 to 10 parts by mass, even more preferably from 0.1 to 6 parts by mass, per 100 parts by mass of the cured product of the liquid resin composition. Here, the quality of the liquid resin composition at the time of hardening is not much reduced, and is reduced by only about 1 to 2% by mass. Since the amount of volatilization of the component (C) is very small, the preferable content of the component (C) in the hardened material is preferable. The content is the same as that in the liquid resin composition. Here, the quantitative analysis of caffeine is carried out by mass spectrometry.

When the liquid resin composition contains a curing accelerator as the component (D), it is preferable because appropriate curing properties are obtained, and the curing accelerator is not particularly limited as long as it is an epoxy resin hardening accelerator, and can be used. Known things. For example, an amine hardening accelerator, a phosphorus hardening accelerator, etc. are mentioned.

Examples of the amine-based hardening accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, and 2-phenylimidazole. Imidazole compound such as 2-phenyl-4-methylimidazole; 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-all three Wait three a compound; a tertiary amine compound such as 1,8-dioxabicyclo[5,4,0]undecene-7 (DBU), trietbylenediamine, benzyldimethylamine, triethanolamine or the like . Among them, preferred is 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-all three , 2-phenyl-4-methylimidazole. Further, examples of the phosphorus-based hardening accelerator include triphenylphosphine, tributylphosphine, tris(p-methylphenyl)phosphine, and tris(nonylphenyl)phosphine. The hardening accelerators may be used singly or in combination of two or more. Further, when an acid anhydride-based curing agent is used as the component (B), an amine-based curing accelerator is preferably used from the viewpoint of curability and storage stability.

The component (D) may be formed by addition of an epoxy resin or the like, or may be a microcapsule type. However, since the manufacturing method of the present invention is to prepare a component of the resin composition for COF sealing, a filter having a mesh size of 1 μm is used to filter the formulation, so that when hardening is performed by addition molding or microcapsule type For accelerators, those with a particle size of less than 1 μm should be used.

When the liquid resin composition contains a coupling agent as the component (E), the component (E) is preferably 3-glycidoxypropyltrimethoxydecane from the viewpoint of adhesion. , 3-aminopropyltrimethoxydecane, vinyltrimethoxydecane, p-styryltrimethoxydecane, 3-methylpropenyloxypropyltrimethoxydecane, 3-propenyloxypropane Trimethoxymethoxyalkyl, 3-ureidopropyltriethoxydecane, 3-mercaptopropyltrimethoxydecane, bis(triethoxymethylpropyl)tetrasulfide, 3-isocyanatepropyltri Ethoxy decane or the like is preferably 3-glycidoxypropyltrimethoxydecane or 3-aminopropyltrimethoxydecane from the viewpoint of adhesion. The commercially available product may, for example, be KBM403, KBE903, KBE9103, etc. manufactured by Shin-Etsu Chemical Co., Ltd. The component (E) may be used singly or in combination of two or more.

The liquid resin composition is preferably a filler containing the component (F). Examples of the component (F) include colloidal silica, hydrophobic cerium oxide, fine silicate, nano silica, and the like; and bentonite (Bentonite) Acetylene black, Ketjen black, etc. are preferably nano cerium oxide from the viewpoint of shape retention after coating. Further, from the viewpoint of the injection property of the liquid resin composition at the time of injection, the (F) component is more preferably an average particle diameter of 0.01 to 20 μm of cerium oxide, and more preferably an average particle diameter of 0.02 to 1 μm. Hey. The commercially available product may, for example, be a fumed silica (product name: R805, average particle diameter: 20 nm) manufactured by Japan Aerosil, and an amorphous cerium oxide made from a Japanese catalyst. (product name: SEAHOSTAR KE-P10, average particle diameter: 100 nm), manufactured by Fuso Chemical Industry Co., Ltd. (product name: SP03B, average particle diameter: 300 nm). Here, the average particle diameter of the nano cerium oxide particles was measured by a dynamic light scattering type nanoparticle (Nanotrac) particle size analyzer. The component (F) may be used singly or in combination of two or more.

When the liquid resin composition further contains the rubber component of the component (G), from the viewpoint of alleviating the stress of the resin composition, preferred (G) components include acrylic rubber, amine ester rubber, and polyoxyethylene rubber. (Silicone rubber), butadiene rubber. Ingredient (G) can be used as a solid. The form is not particularly limited. For example, in the form of particles, powder or ingot, in the case of particles, the average particle diameter is, for example, 10 to 200 nm, preferably 30 to 100 nm, and more preferably 50 to 80 nm. The component (G) can also be used in a liquid state at normal temperature, and examples thereof include polybutadiene having a low average molecular weight, butadiene-acrylonitrile copolymer, polyisoprene, polyoxypropylene, and polydiorgano. Polydiorganosiloxane. Further, the component (G) may be used for a group having a terminal which reacts with an epoxy group, and these may be either solid or liquid. For the commercially available product, for example, ATBN1300-16, CTBN-1008-SP, etc., manufactured by Ube Industries, Ltd., may be mentioned. The component (G) may be used singly or in combination of two or more.

The component (D) is preferably contained in an amount of more than 0.1 part by mass and not more than 5 parts by mass, more preferably 0.2 to 4 parts by mass, more preferably 0.3 to 3.0 parts by mass, per 100 parts by mass of the component (A). When it is 0.1 part by mass or more, the reactivity is good, and when it is 5 parts by mass or less, the moisture resistance reliability is good, and the viscosity increasing ratio is stable.

The component (E) is preferably contained in an amount of from 0.05 to 15 parts by mass, more preferably from 0.1 to 10 parts by mass, per 100 parts by mass of the component (A). When the amount is 0.05 parts by mass or more, the adhesion is improved, and the moisture resistance reliability in the PCT test is further improved. When the amount is 15 parts by mass or less, the foaming of the liquid resin composition is suppressed.

The component (F) is preferably contained in an amount of from 0.1 to 90 parts by mass, more preferably from 0.5 to 40 parts by mass, even more preferably from 1 to 30 parts by mass, per 100 parts by mass of the liquid resin composition. If it is 1 to 30 parts by mass, deterioration of the injectability can be avoided while suppressing an increase in the linear expansion coefficient.

The component (G) is preferably contained in an amount of from 0.1 to 30 parts by mass, more preferably from 0.5 to 25 parts by mass, even more preferably from 1 to 20 parts by mass, per 100 parts by mass of the component (A). When it is 0.1 part by mass or more, the stress of the liquid resin composition is alleviated; and when it is 30 parts by mass or less, the moisture resistance reliability is not lowered.

In the liquid resin composition of the present invention, a pigment such as carbon black, a dye, an antifoaming agent, an antioxidant, a stress relieving agent, other additives, etc. may be repeatedly adjusted as needed within the range not impairing the object of the present invention. .

In the liquid resin composition of the present invention, for example, the components (A) to (C) and other additives may be simultaneously or separately heated, and stirred, melted, mixed, and dispersed. get. The apparatus for mixing, stirring, dispersing, and the like is not particularly limited, and a Mincing Machine equipped with a stirring and heating device, a 3-roll mill (Triple Roll Mill), a ball mill, and a planetary type can be used. A blender (Planetary Mixer), a bead mill (Beads Mill), and the like. Further, these devices may be used in combination as appropriate.

The liquid resin composition of the present invention is preferably from 50 to 2000 mPa·s at a temperature of 25 ° C from the viewpoint of injectability. Here, the viscosity was measured by an E-type viscometer (Model: TVE-22H) manufactured by Toki Sangyo Co., Ltd.

The liquid resin composition of the present invention is formed/coated on a desired position of the substrate via a dispenser, printing, or the like. Here, the liquid resin composition is formed between a substrate such as a flexible wiring board and a semiconductor element, and at least a part of the substrate is connected to the circuit of the substrate.

The hardening of the liquid resin composition of the present invention is preferably carried out at 80 to 300 ° C for 30 to 300 seconds, and from the viewpoint of use as an epoxy sealant, since hardening within 200 seconds improves productivity. Preferably.

Further, a desired material can be used for the semiconductor element or the substrate, and it is preferably a combination of a flip-chip bonded semiconductor element and a COF package substrate.

Thus, the liquid resin composition of the present invention is very suitable for a liquid semiconductor encapsulant, and has a semiconductor device using a flip chip type semiconductor element sealed by the liquid semiconductor encapsulant, and has migration resistance and lead corrosion resistance. Excellent, for high reliability.

(Example)

The present invention has been described by way of examples, but the invention is not limited thereto. Further, unless otherwise indicated, parts and % in the following examples represent parts by mass and % by mass.

[Examples 1 to 18, Comparative Examples 1, 2]

A liquid resin composition (hereinafter referred to as "resin composition") was prepared by the mixing shown in Tables 1 and 2. The resin compositions produced were all in the form of a liquid.

[Evaluation of viscosity]

The viscosity (starting viscosity, unit: mPa.s) of the resin composition just prepared was measured by an E-type viscometer manufactured by Toki Sangyo Co., Ltd. The measurement results of the initial viscosity are shown in Tables 1 and 2. Further, the viscosity of the resin composition after storage for 24 hours or 48 hours at 25 ° C and a relative humidity of 50% was measured, and (viscosity after 24 hours or 48 hours) / (starting viscosity) was taken as a viscosity increase rate (unit: %) ). The results are shown in Tables 1 and 2.

[Evaluation of water absorption rate]

The starting weight of the sample obtained by curing the resin composition prepared at 150 ° C for 60 minutes was set to W ₀ (g), and placed in a PCT test tank (121 ° C ± 2 ° C / humidity 100% / 2 atm) After 20 hours, the mixture was cooled to room temperature, and the weight of the obtained test piece was defined as W ₁ (g), and the water absorption ratio (unit: %) was determined by the following formula.

Water absorption rate = (W _{1 -} W ₀ ) / W ₀ × 100 (unit: %)

The evaluation results of the water absorption rate are shown in Tables 1 and 2.

[Evaluation of flexural modulus]

Between the glass plate coated with the release agent and the glass plate, the resulting resin composition was cured to a sheet of 350 μm at 60 ° C for 60 minutes, and a universal testing machine (AG manufactured by Shimadzu Corporation) was used. -1) Find the bending modulus at room temperature. Further, the measurement was performed at n = 3, and the average value was used. Further, after the film thickness and the width of the test piece were measured at five points, the average value was used for the calculated value. The bending modulus is preferably from 2.0 to 4.0 GPa. The evaluation results of the bending modulus are shown in Tables 1 and 2.

[Evaluation of the amount of extracted Cl ions]

The obtained resin composition was pulverized to a positive square of 5 mm at 150 ° C for 60 minutes. Hardened coating film: 25 cm ^{3 of} ion-exchanged water was added to 2.5 g, placed in a PCT test tank (121 ° C ± 2 ° C / humidity 100% / 2 atm tank) for 20 hours, and then cooled to room temperature to obtain an extract as Test solution. The Cl ion concentration of the extract obtained by the above procedure was measured using an ion chromatograph. The evaluation results of the amount of extracted Cl ions are shown in Tables 1 and 2.

[Investigation evaluation]

Fig. 2 is a schematic view showing a method of evaluating the injectability of the resin composition. First, as shown in FIG. 2(A), a gap 40 of 20 μm is provided on the substrate 20, and a test piece in which a glass plate 30 is fixed to replace the semiconductor element is produced. However, in the case of the substrate 20, a glass substrate is used instead of the flexible substrate. Next, the test piece was placed on a hot plate set to 110 ° C, and as shown in FIG. 2 (B), the produced resin composition 10 was applied to one end of the glass plate 30, as shown in FIG. 2 (C). As shown in the figure, the time taken for the measurement gap 40 to be filled with the resin composition 11 is set to "good" when it is filled for 90 seconds or less. The results of the evaluation of the injectability are shown in Tables 1 and 2.

[Evaluation of migration resistance]

In order to evaluate the migration resistance of the resin composition, a high temperature high humidity test (THB test, High Temperature High Humidity and Bias Test) was carried out. The test method is as follows. Manufactured on a Polyimide Tape substrate having a tin plating (0.2±0.05 μm) copper circuit (pattern width 10 μm, line pitch 15 μm, pattern pitch 25 μm), coated at a thickness of 20 μm The resin composition was treated at 150 ° C for 30 minutes to cure the sealant to prepare a test piece. The test piece was subjected to an ion mobility evaluation system (manufactured by Espec Co., Ltd.), and the change in resistance value when a voltage of DC 60 V was applied under conditions of 110 ° C / humidity of 85% was measured, and when the resistance value was less than 1.00 × 10 ⁷ Ω, it was Limits, evaluate the migration of copper circuits (unit: time). If the resistance value is not lower than the threshold, the test is terminated at a time exceeding 500 hours. The results of the evaluation of migration resistance are shown in Tables 1 and 2. Figures 3 to 7 are photographs after evaluation of migration resistance. Although the photograph is not attached to the scale, as described above, it is a copper circuit having a pattern width of 10 μm and a line pitch of 15 μm. Fig. 3 is a photograph of the first embodiment, the fourth embodiment, the second embodiment, the fifth embodiment, the fourth embodiment, the sixth embodiment, and the seventh embodiment.

[Evaluation of Lead Corrosion Resistance]

The above test piece subjected to the migration resistance evaluation was observed with an optical microscope (model: STM6) manufactured by Olympus at a magnification of 50 times. The corrosion of the circuit is less than one-third of the width of the circuit, which is "○", and that of 1/3 or more is "╳".

[Table 1]

[Table 2]

From Tables 1 and 2, it is understood that all of Examples 1 to 22 have low viscosity increase rates, good injection properties, low water absorption, excellent migration resistance and lead corrosion resistance, and the bending modulus is a desired value. In particular, in Example 21, which contained the components (A) to (E) and (G), the bending modulus was the lowest. In addition, the viscosity increase rate of Example 10 in which 10 parts by mass of the component (C) was added to 100 parts by mass of the liquid resin composition was higher in the examples. On the other hand, Comparative Examples 1 and 2 containing benzotriazole in place of the component (C) have a high viscosity increase rate and poor lead corrosion resistance. Comparing Figs. 3 and 5 of Examples 1, 2, and 4 with Figs. 6 and 7 of Comparative Examples 1 and 2, the lead wires of Figs. 6 and 7 were continuously corroded, and the entire substrate was discolored.

(industrial availability)

The liquid resin composition of the present invention can suppress the viscosity of the liquid resin composition during storage, and can prevent migration of the liquid resin composition after curing, and is particularly suitable for flip chip type semiconductor devices.

1,20. . . Substrate

2. . . anode

3. . . cathode

10, 11. . . Liquid resin composition

30. . . glass plate

40. . . gap

Fig. 1 is a schematic view showing the migration in the case where the electrode is copper (Cu). 1 is a substrate, 2 is an anode, and 3 is a cathode.

Fig. 2 (A) to (C) are schematic views showing a method of evaluating the injectability of the resin composition. 10 and 11 are liquid resin compositions, 20 is a substrate, 30 is a glass plate, and 40 is a gap.

Fig. 3 is a photograph of the resin composition of Example 1 after evaluation of migration resistance.

Fig. 4 is a photograph of the resin composition of Example 2 after evaluation of migration resistance.

Fig. 5 is a photograph after evaluation of migration resistance using the resin composition of Example 4.

Fig. 6 is a photograph after evaluation of migration resistance using the resin composition of Comparative Example 1.

Fig. 7 is a photograph of the resin composition of Comparative Example 2 after evaluation of migration resistance.

1. . . Substrate

2. . . anode

3. . . cathode

Claims (9)

A liquid resin composition comprising: (A) a liquid epoxy resin, (B) a curing agent, and (C) a xanthine represented by the formula (1). (wherein R ₁ , R ₂ and R ₃ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms). The liquid resin composition according to claim 1, wherein the component (C) is at least one selected from the group consisting of caffeine, theophylline, theobromine, and para-xanthine. The liquid resin composition according to claim 1, wherein the (D) hardening accelerator is further contained. The liquid resin composition according to claim 1, wherein the (E) coupling agent is further contained. The liquid resin composition according to claim 1, wherein the (F) filler is further contained. The liquid resin composition according to claim 1, wherein the (G) rubber component is further contained. The cured product of the liquid resin composition according to the first aspect of the invention, wherein the component (C) is 0.05 to 12 parts by mass based on 100 parts by mass of the liquid resin composition. A liquid semiconductor encapsulant comprising the liquid resin composition described in claim 1 of the patent application. A semiconductor device having a flip chip type semiconductor device which is sealed by using a liquid semiconductor encapsulant described in claim 8 of the patent application.